254 M. C. COOKE ON NUCLEATED SPORIDIA. 



During the past week I have examined the slides again, but 

 amongst all the sporidia, whether free or still enclosed in their 

 asci, not a single sporidiurn can be detected in which a nucleus is 

 visible (c). Here then is a problem which requires to be solved. 

 What are these nuclei, and how does glycerine affect them that 

 they disappear? It has been said that they are bubbles of air, to 

 which I cannot at present accede. It has been assumed also that 

 they are of an oleaginous nature, which is more probable. What- 

 ever they may be, does the infiltration of glycerine through the 

 the walls of the sporidia cause absorption of the nuclei, and the 

 reduction of the cell contents to a homogeneous fluid ? Would 

 any other fluid, such as spirit or distilled water, produce the same 

 results ? This I have not at present endeavoured to ascertain, but 

 of one thing I do feel certain that the presence or absence of nuclei 

 in the sporidia of fungi, such as Peziza?, and probably also of 

 Sphcerice should not be relied upon too much. It is evident that 

 they are by no means permanent. This we know to be the case 

 with many species of Sphceria. At an early stage the sporidiurn 

 will contain two nuclei, later the sporidiurn is pseudo-septate 

 from division of the endochrome ; later still, it appears to be de- 

 cidedly septate. These are changes which may be observed in the 

 contents of a . single perithecium. Even later still, the sporidia 

 may acquire a deeply coloured epispore ; but all these changes 

 have not been observed in Peziza. In this latter genus the sporidia 

 are rarely septate, and in Peziza lanuginosa, for instance, although 

 the nuclei are so large and so distinct, a septate sporidiurn has 

 never been seen. I have long been of opinion that nucleate 

 sporidia in Splmria are never permanent, but ultimately become 

 resolved into as many cells, and that the sporidiurn which at first 

 is binucleate, or quadrinucleate, at length becomes uniseptate, or 

 triseptate. In Peziza lanuginosa it does not seem to be a question 

 of age, nor in Peziza generally, hence I have been induced to 

 ventilate the subject in order that more observers may enter upon 

 the examination, and endeavour to arrive at some satisfactory con- 

 clusion. 



